Powder metallurgy processes – Powder metallurgy processes with heating or sintering – Post sintering operation
Patent
1985-01-14
1986-05-27
Lechert, Jr., Stephen J.
Powder metallurgy processes
Powder metallurgy processes with heating or sintering
Post sintering operation
419 28, 419 36, 419 37, 419 47, 419 48, 419 57, 419 60, 75228, 75236, B22F 300
Patent
active
045914818
ABSTRACT:
The present invention discloses a method for densifying previously sintered parts constructed of powdered metals, ceramics or the like to nearly 100% theoretical density. The method of the present invention comprises heating the parts containing binder and hard phase above their liquid phase temperature and then applying a pressure in a predetermined range to the parts for a predetermined period of time and simultaneously maintaining the parts at or above their liquid phase temperature. This pressure range is set so that the pressure is below the pressure necessary to overcome the capillary force acting on the binder to keep the binder from entering the voids but above the pressure necessary to physically move or collapse the microstructure inwardly, thus filling the voids with a homogenous mixture of binder and hard phase. The method of the present invention achieves complete closure of even large voids and the elimination of substantially all porosity within the part.
REFERENCES:
patent: Re31355 (1983-08-01), Rozmus
patent: 3469976 (1969-09-01), Iler
patent: 4063940 (1977-12-01), James
patent: 4142888 (1979-03-01), Rozmus
patent: 4431605 (1984-02-01), Lueth
Lechert Jr. Stephen J.
Ultra-Temp Corporation
LandOfFree
Metallurgical process does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Metallurgical process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Metallurgical process will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1570458